1. Field of the Invention
This invention relates generally to measuring instruments of various kinds and relates specifically to a surveyor's rod used with a transit or other sighting instrument.
2. Description of the Prior Art
Heretofore many efforts have been made to provide surveying rods for use with a transit or other sighting instrument, and most of these rods normally have a height of approximately six to eight feet. Such rods have been provided with indicia representing known units of length. Most surveyor's rods are used by clearing a path or line of sight between the rod and the sighting instrument, and such clearing of the path has required a substantial amount of labor as well as a substantial amount of time.
Some efforts have been made to provide a surveyor's rod having extendable or telescoping sections and having a target or flag at the upper end to assist in taking a sight. Normally, these prior art structures have been complicated and have been limited as to the height which is attainable. Some examples of these prior art structures are shown by the patents to De La Pena U.S. Pat. No. 952,275; Watson U.S. Pat. No. 1,165,820; Chaskin U.S. Pat. No. 2,245,901; Heater U.S. Pat. No. 3,762,058; and British Pat. No. 860,117.